Both Overweight and Obesity imply a condition of excess weight in a human being.
The term Overweight is generally used to indicate the excess weight while Obese refers to excess fat. Being overweight means having more body weight than is considered normal or healthy for one’s age or build. On the other hand, Obesity is the condition of being obese, i.e., excess amount of body fat. While an overweight person will carry excess weight, he may or may not have excess accumulation of fat.
edit Calculating Normal or Healthy Weight
One way to distinguish obesity from merely being overweight is to calculate the BMI (Body mass index). An adult is considered “overweight” when he/she is above their stipulated healthy weight, which varies according to a person’s height and sex. The ideal weight for any adult is believed to correspond to his of her ideal weight from age 20 to 30. An individual is overweight when their BMI is between 25 and 29.9. BMI, a calculation that measures weight relative to height, is the standard used by researchers to define a person’s weight according to their height. An adult with a BMI of 30 or more is considered obese.
Obesity is excess fat compared to lean body mass, or a body weight that is 30 percent over the ideal weight for a specific height. A person is obese when the amount of adipose tissue is sufficiently high. Obesity is a chronic disorder, caused by complex variety of factors.
edit Medical Condition
Medically, obesity is a condition of the body characterized by over accumulation of fat under the skin and around certain of the internal organs. While overweight is being more than the weight for age, sex, and height. Overweight does not necessarily imply excess fat. People like athletes, bodybuilders can be overweight but not obese.
A person may be overweight because of the following reasons: Overeating, sedentary lifestyle, no exercise, metabolic or eating disorder, medical condition, etc. While these factors can also lead to obesity, it can also be caused by social and lifestyle changes, medical problems, hormonal imbalance, genetic condition and can be aggravated by increased intake of food and lack of exercise.
Obesity is a major risk factor for serious health problems including coronary heart disease, [[Systolic vs Diastolic Blood Pressure|high blood pressure], diabetes, hypertension, etc. Though an overweight person also faces a risk of these medical problems but an obese is more susceptible to them.
Obese people are at high risk of depression and other social problems. Obesity is an excess of body fat sufficient to shorten one's life span and make one susceptible to a greater amount of illness than would occur if the body weight were normal. Calorific imbalance that results often develops from a combination of genetic and environmental factors. A combination of an excessive nutrient intake and a sedentary lifestyle are the main cause for the rapid acceleration of obesity.
The safest and most effective way to lose weight in both cases is to reduce calories (balanced diet) and increase physical activity. In excess cases of obesity a person can undergo surgery.